Help- old 5” bench grinder maintenance question

[Shelby7]

I just picked up an old Kmart 5” bench grinder this past weekend made in the USA

Anyways, on the back of it, says “oil” on each side (pictures attached”

Where exactly do you oil and how do you do it?

Best I can tell is to drop some in the middle hole (pic 3) but when I did, it didn’t go down in there really, it just filled up the tiny hole

 

[SeisMec]

Is there a spring loaded seal? Maybe use a straight pick to see if it moves.

 

[joshmodelskidoo]

Probably in those holes. Probably just has bushings vs bearings right there. You can take it apart and look

 

[Shelby7]

Do I have to push it down for oil to go in? It’s bushings

 

[joshmodelskidoo]

I would assume 1 or 2 drops per hole. Just leave the grinder so gravity can do its job. 2 drops might be a little much. Do some googling and see if you can find a manual on it or another grinder like it to find info on

 

[bpjr]

A few drops in each hole is all you need. Back in the day those tiny holes were normal on elec appliances to keep them lubed. 3 in 1 oil cans with the small spout were the norm to lube those holes.

 

[Bacon!]

It is worth the bother to open it up for closer examination.

Considering the age, if it has felt oil reservoirs next to each bushing, it may hold and benefit from significantly more than a couple drops of oil per bushing. The original oil may have turned to varnish by now and a mere couple drops may just turn that into soft varnish... depends on how well it was maintained in recent decades.

Plus, it's a grinder... it could be worthwhile to at least direct some compressor air inside to blow out any grime in there, but personally I'd go the extra step of taking the motor apart if reasonably possible, thorough cleaning, then if all looked good, decide if it would like a new coat of paint or needs the wiring redone.

 

[bpjr]

Did some googling and found this was sold under several different brand names. Probably the same as a JC Penny grinder Model 4030...1970s. The vintage tool web site shows this model with owners manual and exploded parts list. The instructions say it has oil impregnated bronze bushings and to lube after 50 hrs with a couple drops of 20w oil in each hole. These had a safety recall for the elec cord.

 

[Lightning rod]

Its the middle hole with what looks like a ball in the middle
The design is that you push oil past the spring loaded ball plunger so that you wet
A felt pack around a sleeve bearing
The bearing has a hole or cutout to access the oil in the felt pack
Oiling is done by wicking action when the shaft turns
https://www.gitsmfg.com/metric-ball-valve-oilers/

The oilers should always be oriented vertically
If you buy the correct type of bottle , it will make the job easier

https://www.homedepot.ca/product/masters-lubricating-oiler-113ml/1000421127